Senolytic drugs boost protein that protects against effects of aging

 

Senolytics are an emerging class of drugs designed to target zombie-like cells that have stopped dividing and build up in the body as we age, and the past few years have seen some exciting discoveries that demonstrate their potential. Adding another to the list are Mayo Clinic researchers, who have shown that these drugs can protect against aging and its related diseases, by acting on a protein long associated with longevity.

The zombie-like cells involved in this research are known as senescent cells, and their accumulation during aging is associated with a range of diseases. Recent studies have shown that using senolytics to clear them out could serve as new and effective treatments for dementia and diabetes, and also improve health and lifespan more broadly.

The Mayo Clinic team were exploring how senolytics can influence levels of a protein called a-klotho, known to help protect older people from the effects of aging. The role of this protein in the aging process is well established and has placed it at the center of much research in this space, with studies demonstrating how it could help reverse osteoarthritis and regenerate old muscles.

Levels of a-klotho are also known to decrease with age, and studies have shown these declines shorten the lifespan of mice. Conversely, inserting genes that encode for the protein has been shown to increase the lifespan of mice by 30 percent. Boosting its levels in humans has been problematic, however, as its larger size would require it to be administered intravenously. But now the Mayo Clinic scientists believe they have found another route, as senolytic drugs can be administered orally..

They first showed that senescent cells reduce levels of a-klotho in human cells. They then demonstrated that using a combination of senolytic drugs on three different types of mice could counter this and increase levels of a-klotho. This effect was then observed in follow-up experiments on patients with idiopathic pulmonary fibrosis, a lung disease that can cause breathing difficulty, frailty and death.

"We show that there is an avenue for an orally active, small-molecule approach to increase this beneficial protein and also to amplify the action of senolytic drugs," says James Kirkland, M.D., Ph.D., a Mayo Clinic internist and senior author of the study.

The research was published in the journal eBioMedicine.